Blowpipe cutting apparatus



June 13, 1950 A. M. KELLER BLOWPIPE CUTTING APPARATUS 4 Sheets-Sheet 1Original Filed Jan. 15, 1943 F L H S.

I'NVENTOR ARTHUR M. KELLER BY ATTO-RNEY June 13, 1 950 A. M. KELLER2,511,591

' BLOWPIPE CUTTING APPARATUS Original Filed Jail. 15, 1945 4Sheets-Sheet 2 INVENTOR ARTHUR M. KELLER ATTORNEY A. M- KELLER BLOWPIPECUTTING APPARATUS June 13, 1950 4 Sheets-Sheet 3 Original Filed Jan. 15,1943 V d 09 0d A m w Mn mm v M M 56. 405200 ma R 3 l H OH 9H I. V 39%Evan E N A 3 33 8 L 2.2.5. wzEB L law. Nw u o RL Y Y O F. E 55 N R 55% OQ FEE; v W M m O RQ 1&- N R T MB SEE ma 32 l U A mimnou 0 LEE w mu mm m0QE R Y FL N62 #02 A B km MN kw ww b g Wm Patented June 13, 1950 ArthurM. Keller, Livingston, N. J., assignor to The Linde Products Company, acorporaltion of Ohio Continuation of. application; semi: Nor-422349,.

January 15, 194:3;v

'1945, Seria1 N0.;596,787

This applicationzis. .a.continuation, off, applica tionSerial Nol'lzgliiufileddanuary 15,, 1943, now abandoned, for Blowpipe cuttingapparatus by Arthur M.-.Keller.

This invention relates to, apparatus iorther'mochemically. cuttingierrousmetal and the like with oxidizing gas, and more particularly toauto.-

advantages mentioned above as being inherent in .mechanicalshearsk,Ajhand operated. blowpipe is not convenientfor cutting very hot work. Amachine for thermochemically cutting slabs or bars has been, suggestedbut fasteroperation" has been desired. Another suggestion though not foruse with the rolltable, has been a plurality of blowpipos. mountedfromla long beam moved with the blowpipes'in cutting, but open to theobjection that the beam is cumbersome ior substantial spacing of theblowpipes and. the suggestion. is not. adapted tor use in a rolling,mill. I I

.In this invention these disadvantages have been. eliminatedandtthetravel of the work from r,

the roll table hasbeen expedited. It has also" been possible to apply.this invention in those steel mills having. roll tables located close.besidev one another. 7

Specifically one; operator is now enabled to control a pluralityo-f.cutting blowpipes' at spaced dis-' tances along anelongated work pieceby having him control the substantially simultaneous cutting operationof each blow pipe. vEach such 'blowpipe is preferably mounted separatelyfrom one sidecf. the roll table. Much of the cutting cycle may beautomatic in response to a distance controlled limit, switch after thecycle has been manually started. To facilitate operation of work whichmay bet-longitudinally bent or curved within. the. limits of the rolltable, it is possible toinch eachblowpi'pe in either direction to. astarting position. that may be outof alignment withthe rest of the;blowpipesi Anob-ject. is. to expedite, travel of the work'from the rolltable by stopping it less frequently when short, lengths are to be out.Another object is to enable this advantage to accrue when hot work isbeing handled, A. further obiectistoenable such expedition inrolliitable operation to be This application May 30;.

scams; (crass-gee) applied in steel mills having roll tables arrangedlaterally close together. A still further object of the inventi'onis toprovide a machine for thermochemically putting steel slabs and platesections the" shape of which is such that they are diflicult 'to'outwith amechani'cal power cuttensaidmachine having a nicelya'diustablecutting speed, a plate-riding device that is automatically elevated "atthe end of its work severing stroke and re- ;turned'toan initialposition and cutting blowpipe means lac-which preheat and; cutting gasesare supplied during' such Work-severing stroke and automaticallyshut-offat the completion therevof. Yet another object is-to'provideremote controlmeans'foryoperating one or a plurality of such machines inunison, includinga single adjustable means-for precisely setting thecutting speed ofieach of the machines to a common predetermined value,so that work of a given thicknessmay properly'be cut by all saidmachines operatingseparatelyor in unison.

Referringtofthe drawings Fig. 1' isj-a-view' mainly in side elevation ofa plate cut-off machine exemplifying the invention; g Fig. 2 isa-"p'lanView partly insection taken on .line'22 of'Fig; 1; V

Fig. 3 is a fragmentary view partly in vertical section taken on line3-3 of Fig. 1;

I Fig. 4 is airagmentary view partly in section and partly in sideelevation of the-'blowpipe unit;

Fig. 5 is a view mainly in sectiontaken on line 5+5 of'Fig'. 4;

" Fig/6 is'a sectional view taken on line 6-45 of Fig. 1;

,Fig, 7 is a schematic diagram of two cut-off machines associated with asingle plate conveyor table; r IFig-yfi is a wiring diagram of themotor-generator set and one'carriage driving motor; and Fig. 91is awiring diagram of the control circuit. Referring particularly to Figs.'1to 6, a boxtype cross member or support A is rotatably mounted onapedestalB located beside a Work (plate) conveyor table Q. Within oneside of the cross-member A are disposed longitudinal ways oritrac'ks'Dand a roller chainE, the reaches of the chain E extending in parallelrelation to the tracks. Attached to the chain E is a blowpipe carriageFwhich rolls upon and is guided by the tracks D. To the blowpipecarriage F is attached a blowpipe unit G including a work-riding deviceHhaving two wheels I; bearing J; a bracket K adaptedtoaccommodate acutting blowpipe L, i an auxiliary preheat blowpipeM anda pilot lightducer P by a driving motor Q, the speed of such motor being infinitelyadjustable through a ratio of the order of 8 to 1 or greater speed, bycontrol means including a knob R on a control table S, Fig. 7. Thedriving motor Q is energized by means including a generator T, Fig. 8,having an exciter U, the generator and exciter being driven by a motorV. The armature voltage of the'driving motor Q, and hence its speed, isvaried by' adjusting a rheostat W, Fig. 8, in the field circuit of thegenerator T, which rheostat is connected to the knob R. Current to oneor more carriage driving motors Q may thus be supplied by onemotor-generator set VT and in this manner, the; speed of a plurality ofsimilar machines No. 1

and No. 2, Fig. 7, is adjusted by the single field rheostat W. I v v IWhen a cut is completed by the blowpipe unit G, automatic meansincluding a traveling nuttype limit-switch device X, which is driven byI the motor Q, causes all gases to be shut off the 5 X causes the motortostop andthe unit G to be "lowered to an initialposition spaced fromthe work Y. a

The support A comprises a portion In which extends across the table C ata predetermined distance thereabove, anda portion H which extends in theopposite direction so as to counterbalance the portion lll. Thesupport Aconsists of fabricated metal plates, as shown, and is mounted to turnhorizontally in suitable bearing means l2 on the pedestal B, but ifdesired it may comprise a beam supported at both ends by fixed ormovable members sothatthe beam can be moved longitudinally ortransversely or both with respect to the conveyor table C, in order tocause the blowpipe unit G to travel either at right angles or obliquelyof the direction of movement of the work Y on the table C, or in orderto tilt the path of travel of the carriage F from the horizontal. Themotor Q and speed reducer P are disposed on the support A away from thetable C so as to protect them from the heat of the work Y which may beat a rolling temperature during the severing action of the machine. Thehousing may be provided with any suitable heat insulation, if desired.Shafts l5'and I6 of the motor Q v and speed reducer P are :connected bya flexible coupling The speed reducer drives a shaft l8 on which keyeda'driving sprocket l9 for-the chain E, and a bevel gear 2|] which mesheswith a bevel gear 2| keyed to shaft 22 of the limit-switch device X. Thelatteris disposed within-a suitable box 23 mounted on thesupport A. Adriven sprocket 24 for the chain E is rotatably mounted on the support Anear the outer end of portion It), so that the work severing and returnstrokes of the carriage F are of suflicient length to cut any'width ofwork Y on the table C, the driving motor Q being of the reversible typefor advancing and retracting the carriage F through thechain E. The

longitudinal reaches 25, 25 of the chain E slide on longitudinal shelves26, 26 secured to a web 2! of a laterally openingchannel member of thesupport A. The channel memberj28 has flanges 29, 29 on the inner sidesof which are secured the tracks D, D, the upper track being rectangularin cross-section, and the lower track having a tapered top to provideinclined treads 36, 30, Fig. 3.

The carriage F comprises a body 3| which is made to travel within thechannel member 28 and is provided with rollers 32 and 33 hearing on theinner side of the upper track, and the inclined treads 30 of the lowertracks, respectively. Up-

rights 34 On the body 3| cooperate with the outer side of the uppertrack to prevent inward tilting of the body 3| with respect to thechannel mem-j ber 28. The. body3| is connected to the lower reach of thechain E by means including a stud 35 which projects from the body 3|.Connected to the body 3| by screws 36 is a bracket 31 including a shortcylindrical bar 38 on which is keyed amember 39 having an upwardly andrearwardly extending portion 40 for supporting the pneumatic device 0,and a downwardly extending portion 4| for supporting the work-ridingdevice H. The pneumaticdevice 0 comprises a cylinder 42 hung from theportion 40 by a pin 43 so that the device 0 is free to swing about suchpin. Within the cylinder is a double-acting piston to whichisconnected adepending rod 44.

The lower end portion of the rod 44 extends through an opening 45 in anarm 46 of the workriding device H, and is provided with a ring 4! heldin place by a nut 48 for engaging the arm 46 when the rod 44 is raisedto swing upwardly the work-riding device H.

The arm 46 of the work-riding device is keyed .to a shaft 48the'opposite ends of which are supported by shaft seals 49 and rollerbearings 56 in flanges 5|, 5| of the portion 4| of member 39. Thebearings and seals are held in place and sealed by covers 52, 52 securedto the flanges 5| by screws 53. The arm '46 is limited in its downwardswing by an adjustable stop 54 consisting of a screw which is threadedto 2. lug 55 constituting a part of portion 4| of member 39. The screw54 is secured inadjusted position by a nut 56. By adjusting the stop 54,the lowermost position of the arm 46 may be fixed in accordance with thethickness of the work Y on the table 0. Connected to the free end'of arm46 is a frame 51 having spaced portions 58, 58 constituting bearings forthe wheels I, I which are adapted to ride on the upper surface of thework Y during the work severing stroke of the carriage F. The frame 51is connected to the arm 46 by transverse bolts 59 and 60, thearrangement being such that the position of the frame and drag angle ofthe cutting stream discharged by the blowpipe L, may be adjusted aboutthe axis of the bolt 59.

Mounted on the frame 51 is the bracket K having spaced sleeves 6|, 6|through which the cutting blowpipe L extends.

The blowpipe L is secured in adjusted axial position by clamps 62, 62 onthesleeves. Each clamp consists of annular jaws 63 and 64 fitting atransverse hole 65 in the bracket K, a screw 66 threaded to the jaw 64and extending through the jaw 63, and a handle 61. The jaws 63 and 64have curved blowpipe engaging surfaces, as shown in Fig. 6. To preventthe blowpipe L from slipping downwardly from adjusted position in thesleeves 6|, a split collar 68 is secured to the blowpipe by a bolt 69and engages the top of the upper sleeve. The pilot light burner N issecured to the bracket K in axially adjusted position by a lever 19 andscrew threaded to a socket in each of the sleeves 6|.

The auxiliary preheat blowpipe M is also secured in axially adjustedposition on the bracket K.

a simmer The.- cemeliosmcmdes- 1a,heaininisolating: shield xlz. for thecylinder: lzgswhichiprotents; the latt'er from. theiheatr ofithematic-SE1; it at a; rollingxtemperatme, andifromtthe heat;resultingfrromjthe operationof the blowpines andther mochemicalreactioniof. an oxidizing; gas. stream with fertousimetal: duringithei cuttingoperation.

' Mounted on; the suoportA-withinra;housing:1-3 having" a. hinged cover2 t4 isz-a. panel 113,. 7, which supportsascooling .watensupplm-conduitH,

apreheat acetylene; conduit-15,. .apreheat oxygen conduit: IGpa cuttingoxygen ccnduiti'tl, a compressed air supply'conduifi "Landa'coolingrwater apreheat oxygen-valve 82; acutting oxygen valve 83, apreheat oxygen pressure regulator' fl, and

a ccmpressedair valvea 8:5; The latter'is-connected to the cylinden H ofthepneumatic. device O-by a: blowpiperaising conduitflianda loweringconduit. 8?, the supply or? compressed air being controlled by ayalve Mi'n-the conduit 'llt. A -pilot 1 light acetylene conduit 89; -'and-: anauxiliary preheat acetylene conduit 9!; micron auxiliary preheat oxygencondult'9 l,*Fig. I, may also be medial-I y supported the-panel li, butthey: are

omitted from Fig- 7ito-avoidconfusionf The pilot burner r is 1providedwith a needle valve '92,

and the cutting tozch L; is proymedawithamacetyi lene needle valve 93,a; preheat: oxygen valve; 9'4,

and acutting oxygen valve" 9 Fig:

As shown in Fig. "I; the'preheat: oxygenlinef'tfi and the cutting oxygenline TI areiprovidect with separators sfi and 91": whil'e' the preheat:acetylene linelfiis provided with-'a'hydraulic back pressure vaIve 98.The cuttineoxygen line ll-"is also'pxzovided witha cutting; oxygenpressureregulator': 39 having a handle FOG-and an indicator IM- on thecontrortable or-board S. 'I'he 'board S-a1s0"con tainseight: manuallyoperable pushsbnttons 9 I102, M3, M4 05, IE6, lM,-'Hl8-'amt' l'lls ioi"controlling suitable electrical circuitsto start onstop the carri'age M,to 'purge the cuttingblowpipe' :lines of riage 31 and to starterstopithe cutting stroke-of thecarriage F. "The'cutting machlneNmimayheduplicated by thema'chine No.12, as=-shown, with respect to theconveyorC, in which case each cutting machine isprovl'dediiwi-thasirnilai: control boards. The carriages bf each cutting machine areenergizedby'thecommort IiIOtOIS+ generator set VTto secure uniformcutting speeds;

As'shown inFig. 8;,tho'genetatonT is mechani cally coupled tothe-motorV" to provide: the desired motor-generator set; The; motor V,- showncycle, 220/440 volt-alternating current type motor. The circuit. of" themotor includes a. starting switch H 3 connected tothepush button I82011- the board S, astopping switch'l M connectedrto the push-button I03,and a line-starterf-relay H5". The latter. is: protected by overloadrelay contacts l lo; no and operates. switches. H1: whenenergizedi'bythe closure of themanually operable switch ii i 3, thecircuit: being'energized through. a triple-pole. knife switch I; [8irom-asuitablesource oi alternating current."supply.v Thirty-amperefuses. is 1:9 also protect: theacircuit of the: motor. V

from clamaeewduea tozexcessive cmzrent. Shooters residual'gases, to inchforward or reversethecarm... I10 ateiincluded .initwo ofithe three.lines-to Lthemotox 1V foriopeninethe overload; relayconfimts; Hi in'heeventlot anoverload. Thuswhen staitting, button I;OZ;;is -pushed,.assuming the safetyswitch itfinto; beclosed, the; switch H3 is.clbseicausingqthe relay. [-15 to be. energized. This closesswitches:tlrkandcausesthe.motor V to be enemizedvand remain :soafter-thepush-button tflsisixeleasedt. Theimotozz V hide-energized by pushinejthestop-button. Hi3, causing; therelay Hi5 tobe die-energized. Thisresults-in the open.- ing oi; the'switches. H1. and. the stopping; ofthe .i'mQtQITVQI 'jf'lhevgenerator .T- on thermotor-generator setis ra-2.3.0; volts 2 vkilowatt, direct current type. gen.- eratoni having: afield winding i2| adapted. to; be energized:bytheenciter generator-U,which is also driven-. by: the motor? The exciterU-ihasa series fieldwindingtiwin'the output' cincuit 24., I25; l ishmte fieldi-windingrtzltconnected to such :ciizcnit. through, :an -adiustable resistor 1.2.1.iTEhe goutnuo circuit 'of the excitcr U con-- nected \to -the-inputcircuit 128,. E29,; otthe generator '1'. through 2-a-mperefuses I30;1.50. mhe-sencxator T has .aflelid winding m; shunted Joya wfl-ohmfielclbli schatge resistor, notrshown, endzgconncctcdto theinputcircuit-through a potentiometer rheostat. -l :32- having :a variabletape 1%; and: potentiometer H4. having j an ad- .l staiblentan 335.Themaximum resistance of the-potentiometer A is 3'bUHt..- l6o0' ohms.and haAt QE the; potentiometer 1 H2, about. 11500 ohms. The variabletap. I 33 is controlled by the; knob R having; at cutting-speed?"scale-1 tel; on their control table-fif'ig; 'Lhe. cincuit R1 thevariable-tap i373 inoludesuavswitoh lizladalltcd to be. closed when; a:cutting, relay b391,. Fig. .9, is energized. 'bThe-circuiti'to-theadjustable/tap [:35 likewise includes: aeswitch l All-adapted to beclosed: whenia retraction? relay H. his: energized.

-'.Thc.-:0I1tm1fi circuit H82,- l4-3; of the. generator: T nfihlfl fi:Dmtective "fuses [Mo 1144* "and a series :fieldkwinding; I45,.Gormected tojoutput circuit 1142,; :31. lsr the; carriage; driving--motor Q- which drives; thesblowpipezcarriager F! The motor- Q is--aj'.-21.3.Q-*-4volt,.izehorsepowet; reversible directourrrentmotos-hayinga series fieldwinding M6 :andi-axshuntrfieldiwindingilgt tl, The. latter is connected --:directly-c-tor the.generator output. circuiir Mk1 tarwhiie former-is connectedto the'"output -cincnit :through. :ontting' switches M18,

l'kfiiqandi =-iretractiswitches M19, [49+ Whenthe 14:87am;closedithemotorQ drives the carriageracizossither wonkin one direction to cutvthe; batter, an-wwheir theswitohes i 49: are closed :theamoten Q;drives: the carriage in the opposite :dirtectiomtoteturnzit to:anzinitialrposition. The armature circuit offithemotorQis:provided with:aidynamiobrakine resistor 50 around which is ashuntedta;dynamioibraking illor voltl relay [-5]. Connected across the230-?VOH} direct current generatoroutput lines: t4.2 M3: is theshuntcoil: of a "dynamic? braking-relay 52; in series: with contacts 1.:53of=thexauniliary dynamicbraking relay [5%.

The relays i? and lit'operate anormally closed swit'ehrhil: mythic.control: circuit; Fig. 9; when therelay l'iatis energized the-switch I54 isopene'd, when relay lfB-Z is. energized; then switch 554 isclosediThe switch 153 is closed: and auxiliary dynamic bra-hing switch 155. inthe armature I circiiiti'of the motor: Q is opened-by the. energize,-ti'on-ot-an auxiliary-braking relay I556. in the. con-"tnolicitcuioiFigs.

Asrshowxt. in Fig.29; the. control circuit I 51,; [58 is M connected toav-sourcex. of; 220-vo1t,-"60 cycle, 1-

phase, alternating" current 'by switches I 59,. "I 59 through'10-ampere'fuses 160,160. The control closed, energizing a preheatacetylene valve coil I62 which opens the preheat acetylene valve 8|.Acetylene thereupon flows th'rough'the line 15. At the same time; a'preheat'time delay relay I63 is energized. After a predetermined timedelay switch I64 is' closed which causes a preheat o ygen' valve coil I65 to be energized. This opens the preheat'oxygen 'valve82,'causingoxygen to flow through the line 16. The preheat oxygen andacetylene are mixed in the blowpipe L (and also in theauxiliarypreheating blowpipe M) and the mixed gas jets are ignited-bythe pilot lightburner'N. After the lower edge of the ferrous metalwork'Y' is heated to its ignition temperature by these mixed burninggases, the out button I08 is pushed, c losing a switch 166' whichresults in the energi z'ation of a cutting relay I 61. This'closescutting switches I68, I69, I10, "I, I12 and opens-switch I13. Theclosure of the switch I68 energizes the auxiliary dynamic brakin relayI56 which closes switch I53, Fig. 8. This energizes relay I52 whichopens switch l55.- Atthe same time the closure of switch I69 causes therelays I39; I39 to be energized; closing-switches I48,

' I48, which results in the energization of the driving motor Q andmovement o'f'th'e carriage F across the work Y at a predeterminedconstant speed depending upon the adjustment of the generatorpotentiometer through "the knob B, Fig; 7.

Closure of the switches I10 and I 1| maintains the preheat valve coilsI62 and I65 energized and energizes a cutting oxygen valve coil I14. Thecutting oxygen valve coil I14'ma ybe"energized also by closing amanually operable switch 212 by means of push button I inthe'controlcircuit. This opens the cutting oxygen valve 83,

causing cutting 'oxygen' to flow through the' line 11 to the blowpipe L.As the blowpipe L travels above the work Y, the cutting oxygenstreamdischarged thereby thermochemically severs the work Y. When the blowpipecarriage F reaches --the end of its cutting stroke, the limit-switchdevice Xoperates, opening a cutting limit switch I15. This de-energizesrelay I 61, causing switches I68, I69, I10, I'Il and H2 toopen,-andswitch I13 to close The preheat and cutting relays arethereupon de-energized and the preheat and cutting gases to theblowpipes are automatically shut-01f. At the same time, the carriagedriving motor Q is stopped with dynamic braking, relay I11 is energizedbecause limit switch I16 is'closed reverse direction to'return thecarriage F to'its initial position, where' the retract limit switch 116is opened. Cutting limit switch I15 is reclosed immediately as thecarriage F moves in the retract direction. The control circuit then actsto stop the motor Q, and lower the device The motor Qiis energized toinch the carriage into. a desired position by pushing either the inchforward button I or the inch reverse button I06, Fig. '7. The former(I05) is connected to switches I84 and I85 in the control cir- "75 8c1J.it' ,-Fi'g. -9;*a'nd-ithe ="latte'rt('I06)' is connected to switchesI86} I81and .l89.' The"term".t0 inch is a wellknown term'in'the artreferring to a control 'for a motoradaptedfi for manual starting. :and

automatic stopping in response to its movement,

so that the advance is by only a small increment each time a buttonispressed, or it may be a movement requiring 'the'starting button to beheld when stoppingoc'curs on removal of the-finger. In each type'ofinching apparatus the control is manual and for the'purpose of movingsomething only a small amount without danger of overrunningl'" The stopbutton I09 is connected to switches I90 and 'I9I in tl'ie controlcircuit sov that the motor Q-will run in. the ..retract" direction todrive icarriageqFtocits' fully. retracted position. Also,-al1gases'areshut off; The control circuit is provided with a; safetyrz'switch I92which is adapted to be opened by an overload resistor I 93 connectingtheinput'circuit of the motor Q to'the. output circuit'l42, 1480i thegenerator T.

Briefly, the seq'uenceof operation is as follows: For initiating 1a cut,the-,zblowpipe unit G is brought to the starting positionlby, operatingthe inching buttons I05 and I 06;' Then, with the unit G inproperpreheat position, the preheat gases are turnedon byjdepressing thepreheat button I01.' The blowpipe L being in lowered position, with thewheels! :in contact with the upper edge of theplate'Y; the resultingpreheat flames impinge on the lower corner of the plate and also on theuppenedge'of the plate. After the; work has been properly'preheated, thecut button I08, is pressed; This simultaneously turns 'onthe cuttingoxygen and starts the motor Q-in the forward direction at the selectedcutting speed. When the'cutis completed, automatic operation of thelimit-switch I15 causes all gases to be shut off, the "blowpipe unit Gto be raised to a position-spaced above the'top of the conveyor table C,and reverses the-motor Q' at its maximum speed. Upon the blowpipe unit Greaching its fully retracted position, automatic operation of the limitswitch I16 stops-the motor Q, and causes the blowpipe unit G to belowered to an initial-position outside of the roll table 0,completing'the'operati-ng cycle of the machine.

By the-use of the, common motor-generator set anda' separate carriagedriving motor Q for invention is applicable to the cutting'of either hot(rolling temperatures) or cold (room temperatures) steel where anoxy-fuel gas preheat mixture is usedyand thepline of cut may be at rightangles or at an oblique angle tothe roll line.

.'I claim:

1. Thecombinatiorr with a roll conveyor table along which elongated hotmetal'work is adapted 7 0* work isstop'p'ed, with minimum distortion ofthe cut ends. of th'ework, and without requiring a separateoperatorfor-each blowpipe, said improvement comprising a cutting blowpipe ateach spaced location, a transverse beam at each such location from whichthe blowpipe is suspended, a separate support for each transverse beam,each blowpipe having a device for preheating the work before eachcutting blowpipe begins its operation, separate mechanism on each beamfor moving each blowpipe transversely of the work, means for supplyinggas to each blowpipe, mechanism for automatically cutting oil the gassupply from the blowpipes in response to completion of a cuttingoperation, means for retracting each blowpipe transversely of the outwork, and manually controlled mechanism for beginning a cutting cycle ofeach blowpipe, each manually controlled mechanism including a pushbutton controlled inching device for actuating the blowpipe whereby oneor more or all of the blowpipes may be inched substantiallysimultaneously in either direction along its supporting beam, to bringthe plurality of blowpipes into starting position irrespective ofwhether or not the work may be laterally bent out of alignment, thecontrols of each of said manually controlled mechanisms being juxtaposedfor actuation closely together in time by an operator in one position,whereby the movement of the work along the roll table is expedited byhaving fewer stops for cutting.

2. The combination according to claim 1 in which the support for eachblowpipe supporting beam is arranged on the same side of the roll tableas each other such support.

ARTHUR M. KELLER.

REFERENCES CITED The following references are of record in the file ofthis patent:

10 UNITED STATES PATENTS Number Name Date 520,748 Bancroft May 29, 1894644,666 Day Mar. 6, 1900 696,247 Leonard Mar. 25, 1902 934,301 GeistSept. 14, 1909 1,479,989 Harris Jan. 8, 1924 1,773,712. Wiard Aug. 19,1930 1,972,372 Borden Sept. 4, 1934 2,143,969 Biggert, Jr. Jan. 17, 193920 2,214,571 Baston et a1 Sept. 10, 1940 2,223,452 Jones et a1. Dec. 3,1940 2,277,054 Anderson Mar. 24, 1942 2,283,346 Bucknam et a1 May 19,1942 2,293,853 Rountree Aug. 25, 1942 2,317,239 Yoch Apr. 20, 1943FOREIGN PATENTS Number Country Date 262,986 Great Britain Oct. 7, 1926

